Consumers who can legally validly access a public performance of broadcast video content are allowed to make copies of that content for their own time shifted private viewing. A Personal Video Recorder (PVR) is a system that may comprise hardware and software, in such case called a Digital Video Recorder (DVR), which enables its user to technically execute this time shifting right. This copyright exception allowing legally validly receivable broadcast content to be copied for own private performance has become a basic principle of copyright law that has been adopted internationally, in technology neutral law and legislation, forming the legal basis for PVR, DVR and recently also cloud DVR systems.
Under certain interpretations of international copyright and broadcast law a personal copy of broadcast content should be stored in separate memory space in order to uniquely identify the copy as personal. Storing uncompressed personal video copies for a big number of viewers requires a lot of storage space. Therefore, an efficient compression technique is required in CVRs.
Different generations of the most popular video codecs according to increasing compression ratio: 1) Motion JPEG: storage of all frames, look for redundancy within 1 frame; 2) MPEG2 video: looking for redundancy over time, in relation to the previous frame; and 3) H264 video: looking for redundancy over time, in relation to maximum 21 previous or next frames or part of frames. However, using only the existing compression algorithms, still poses the problem of massive storage capacity for storing the same TV program for multiple viewers in the cloud, in CVRs.
Accordingly, a need exists for a system and technique for more efficient compression of video data for use with a Collaborative Video Recorder.